Proficiency test scheme for histamine analysis in fishery products in Morocco using the fluorometric method and comparison of results with those obtained with the HPLC reference method

¹ ONSSA, Regional Laboratory of Analysis and Research, Casablanca, Morocco
² CUMAREX AS, Industrial Area, Tétouan, Morocco
³ ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Boulogne-sur-Mer Laboratory for Fishery Products, France
⁴ ANSES Maisons-Alfort Laboratory for Food Safety, Unit for Mineral and Inorganic Contaminants in the Environment, France
⁵ AFNOR, EURL, Œnologues de France, 1 rue des Cèdres, 33290 Blanquefort, France

^⋆ Correspondence: abderrazzak57@gmail.com

Received: 31 March 2011
Accepted: 7 November 2011

Abstract

A Proficiency Test Scheme (PTS) for histamine analysis in fishery products using the Lerke and Bell (1976) fluorometric method was conducted in 26 different Moroccan laboratories. The goal of this PTS was to assess the abilities of a network of seven government laboratories and 19 laboratories performing auto-controls on fish processing units in Morocco. The samples used in the PTS were prepared from canned ground mackerel flesh, to which was added two significant concentrations (levels 1 and 2) of histamine. The homogeneity of the PTS samples was verified by a repeatability test and their stability by an intermediate fidelity test. The Cochran test was used to eradicate anomalous scattering and the Grubbs test to eradicate the anomalous averages observed in the results of the participating laboratories. The average and the usual deviations determined for levels 1 and 2 were used to calculate the Z-scores. For level 1 therefore, 23 out of 26 laboratories had satisfactory PTS results, and for level 2, 21 out of 26 laboratories had satisfactory PTS results. An analysis of the PTS samples using the HPLC reference method gave similar results for levels 1 and 2.